Gyro precessing means



Jan- 8, 1952 A. w. FISCHER ET AL 2,581,476

GYROPRECESSING MEANS Filed May 3, 1945 5 Sheets-$heet l Snoentors Jan-8, 1952 A. w. FISCHER ET Al. 2,581,476

GYRoPREcEssING MEANS ,Filed May s, 1945 5 sheets-snee+u 2 -gZ ya g d 7 o'J O /2 ga q v 'n l J /f S C@ V y *MQ yf ISnventorS M( s QL Gtomegs Jan.8, 1952 A. W. FISCHER ET AL 2,581,476

GYROPRECESSING MEANS Filed May 3, 1945 5 Sheecs-Sheet 3 Ennentors y,c2255?? Mgg-M (E Jan- 8, 19542 A. w. FISCHER ET A1. 2,581,476

GYROPRECESSING MEANS gy' f diag?? Qyfflm Jan. 8, 1952 Filed May 5, 1945A. w. FISCHER ET AL GYROPRECESSING MEANS 5 Sheets-Sheet 5 7/ /0/ if frd, I, i

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Patented Jan. 8, 1952 `GrYRO PRECESSING MEANS Albert kW. Fischer,Highland Park, and Archie D. McDuiiie, Berkley, Mich., assignors toGeneral Motors Corporation, Detroit, Mich., a corporation `of DeluawareApplication May 3, 1945, Serial No. 591,796

y 5 Claims.

The present invention generally relates to directional controllingmechanisms and more particularly relates to directional controllingsystem of the gyroscopic type.

The principal object of the invention is to provide a simple directionalcontrol system for an air-borne ship including a gyroscope having simpleelectromagnetic precessing and erection controlling means by which thedirection of the ship may be remotely controlled and which is notsubject to errors caused by magnetic leakage from these means or by rolland pitch of the ship.

Two modcations of control means by which the above object is attainedand other features thereof will become apparent by reference to thefollowing detailed description and drawings illustrating the systems.

Figures 1 and 2 of the drawings are vertical elevation views taken atright angles to each other, with parts broken away, of one form ofgyroscopic directional controlling means; Figure 1 being taken on lineI-I of Figure 2 and Figure 2 being taken on line 2-2 of Figure l, withparts broken away.

Figure 3 is a cross-sectional view taken on line 3-3 of Figure l, withparts broken away.

Figure 4 is a cross-sectional View taken on line 4 4 of Figure 1.

Figures 5 and 6 are vertical elevation views taken at right angles toeach other with parts broken away, of another form of gyroscopiccontrolling means.

Figure '7 is a cross-sectional View taken on line 1-1 of Figure 6 withparts broken away.

Figure 8 is an enlarged cross-sectional view taken on line 8-8 of Figure5, with parts broken away to show a detail of part of the mechanism tobetter advantage.

Figures 9 and 10 are schematic views of two control systems and thecontrolling and control connections between the elements of the systems.The system shown in Figure 9 includes the gyroscopic controlling meansshown in Figures 1 to 4 and the system shown in Figure l includes thegyroscopic controlling means shown in Figures to 8.

'l The gyroscopc controlling means shown in Figures 1 to 4 includes anelectric driving motor l directly connected to a gyroscope rotor 3supported for rotation about a horizontal axis in an inner gimbal member5. The inner gimbal member is pivoted on a horizontal axis transverse tothe rotor axis in an outer gimbal member l which is pivoted about avertical axis in a gyroscope frame member 9 provided with a removablecap 2 Il. The base I3 of the frame 9 is adapted to be mounted on a shipfor controlling the direction thereof so that the rotor axis ismaintained parallel to the transverse center line of the ship.

Means comprising two ironclad solenoids l5 and l1 and plungers I9 and 2lfreely movable therein are provided between the outer and inner gimbalsfor causing precession of the gyroscope rotor and gimbals about thevertical axis. The solenoids are mounted equidistant and on oppositesides of the vertical axis of the outer gimbal with their axes parallelto the rotor axis and the arcuate plungers are mounted on diagonallyopposite corners of the inner gimbal with their free ends freely movablein the solenoids. The free end 22 of each of the plungers is ofidentical stepped" or shaded form, the transverse width of the endsincreasing in steps, as best shown in Figure 2, in order to provideconstant pull on each by a respective solenoid, when either isenergized, and therefore constant torque in either direction between theouter and inner gimbals for a limited range of relative movement betweenthe gimbals.

Means comprising an erection motor 23 secured on the base i3 of theframe for rotating the outer gimbal about its axis is provided forcausing erection of the inner gimbal so that the rotor axis is caused tobe maintained parallel to the base of the frame 9 at all times. Theerectie-n motor is connected by reduction gearing, one gear 25 of whichis shown meshing with a sector gear 2l which is rotatable on the outergimbal lower pivot support 29 about an :axis coaxial with that of theouter gimbal, as best illustrated in Figures 1 and 4. A depending lug 3lsecured to the lower portion of the outer gimbal extends betweenadjacent radial projections of the sector gear 21. Each of two identicalcompression springs 33 is placed between a projection on the sector gearand the adjacent end of the lug 3| to provide a flexible drivingconnection between the erection motor and the outer gimbal.

Current collecting means are provided between the frame and the gimbalmembers to connect the above described precession and erection means tocontrol means and to power operated steering mechanism of the ship whichis controlled by precession of the gimbals about the vertical axisrelative to the frame. These collecting means, the control means and thesteering mechanism and the connections therebetween are best shownschematically in Figure 9.

Y' 3 a radio receiver 35 including` suitable filter and amplifier meansand an antenna 31 so that when a signal of a certain frequency isreceived the winding of a relay -39 is energized and when a differentfrequency signal is received the winding o another relay Si isenergized. One winding terminal of each of these relays is grounded andeach of the other terminals is connected by a separate wire to separateoutput terminals of the receiver.

Y These wires are indicated by the numerals 43 and 45. `One inputterminal of the receiverv is connected to ground and the other input'terminal is connected to a positive wire 411 which is conf nected tothe positive terminal of a battery 4B having the negative terminalgrounded. `The movable contacts of each of the relays 39-41 are alsoconnected to the positive wire 41 and the fixed contact of each isconnectedto one terminal of each of the precessing solenoids by ,meansof separate current collecting means. The other winding terminals ofthesolenoids are grounded on the outer gimbal.

One of these current collecting means-s indicated generally at 49. Thiscurrent collecting means includes two springfflngers, provided withengaging contacts located on the axis of the outer girnbal, andconnectedin series between the n xed contact of the relay 39 and one windingterminal of precessing solenoid l5 by wires 59 and 5l. The otherterminalY of the winding is grounded on the outer gimbal. -One of thesespring fingers is secured on Ian insulator'carried by the frame 9 andthe other finger is secured to an insulator carried by the outer -gimbal7i. Other identical current collecting means mounted in identical mannerare indicated generally at 53, 55, 51 and 59.

rIi'he current collecting means 53 is connected Y in series between the-xed contact of the relay lliY and one winding terminal of theprecessing solenoid l1 by wires l6) and El. The other wind-v ingtermin-al of the solenoid I1 is also grounded on the outer gimbal. d

The current collecting means 55 is connected in series with the windingof a reversing relay 62 between the positive wire 41 and a spring finger53 by wires 64 and E5. The finger 53 and another spring finger 61 areeach secured by an insulator to the outer girnbal and these fingerscooperate with contact disks 69 and 1I secured to a disk insulator12carried on 'the lower end of a shaft 13 which is supported for rotationinthe 4frame cap H about a vertical axis coaxial with that of the outergimbal axis. The nnger `-53 is positioned to engage either the contactdisk 59 or the contact disk 1i or adjacent ends of both contact disksupon relative movement between the outer gimbal and shaft 13 and the'finger 61,'is grounded on the outer gimbal and is positioned to bear onthe Contact disk 59 at a point coaxial with the outer gimbal verticalaxis'. The contact disk 99 is grounded to the frame cap l l by aflexible Wire 15. v

The current collecting means 51 and 59 are connected in series withanother current collecting means generally indicated at 11. The currentcollecting means 11 comprises contact disks 19 and 89 secured to aninsulator disk which is supported on the outer gimbal in coaxialrelation with the inner gimbal axis and two spring n ngers- 8| and 82bearing thereon which are'secured to an insulator carried by the innergimbal. nnger Bl bears on the contact disk 19. at a `point on the axisof the inner-gimbal and the'current collecting means 51 is :connectedbetween-the The positive wire 41 and the contact disk'19 by the wires 83and 34. The other spring finger 82 is adapted to bear on either or onthe adjacent ends of the contact disks 19 and 80. The current collectingmeans 59 is connected in series by wires 35 4and 86 between the contactdisk 99 and one winding terminalof another reversing relay B1, havingthe othertfermiriall grounded. Both of the spring fingers 8| and 82 areconnected by a wire `98 to a terminal of the rotor motor l, the otherterminal of which is connected to ground through a lwire '89 .andanother current collecting means indicatedgenerallyat 99. This meansincludes ya contactf'lllV on the outer gimbal and a spring finger92`groundedon the inner gimbal and bearing on the contact 9| at a pointlocated on the horizontal1 axis of the inner gimbal.

T'li'e'reversing -relay 62 controls reversal of an electricsteeringmotor 93 which is operably connected by irreversible gearing to therudder 55 of the ship. An ,arm91isgeared to. the rudder and is connectedbyalink 99` to an arm itil secured to the shaft 1?lv and the arms andlink serve as a follow-up linkage. The field winding of the steeringmotor is connected between the positive wire 41 and ground and thearmature is connectedacro'ss the two movable contacts `of the relay 52which normally contact the central `and lower xed relay contacts and aremoved'u'p'- wardly into contact with the central and upper xed lrelaycontacts when the winding of the relay is' energized. The fixedcentralrelay Acontact is connected to'fthe positive Wire 41 and jtheother two xedrelay.y contacts are grounded so that with the movablecontacts in the normal position the motor is' energized for rotation inone direction and when the relaywi'nding is ener'- gized and thearmature contacts are moved .up wardly the motor is energized forrotation in the opposite direction of rotation.

'IhefreversingA relay 81 is of similar form to' the steering motorreversing relay 62 and serves to reverse therotation' of the erectionmotorlS. The eld 'winding'o 'the erection motor is connected between thepositive conductor 41 and ground, the armature is connected across themovable contacts" ofthe relay 81 which normally contact thecentral andlower fixed relay contacts and are moved upwardly into contact with thecentral andiupper ,fixed relay contacts to cause reversal of theerection motor when the relay winding Ais energized as the central fixedcontact is connected to the positive wire 47 vand the other xed contactsare' grounded 'in the same manner as the reversing relayr 62 for thesteering motor93.

The ulceration of the above described control system andgyroscopic'directional control'means is as follows: Y Y Y Y With thegyroscope rotor 3 driven by the motor l about a horizontal axistransverse to the longitudinal kcenter line of the ship Vcorrespondingto the course setting any slight movement of the shipto the'right of thecourse causes the shaft 13 and disk contacts ,(59V and vH to turnclockwise withv reference to the outer gimbal, due tothe linkageconnection between the shaft Yand rudder 95. This causesthegcontactrdisk 'il to move into contact with the spring nnger -63carried by :the cuter gmbal to disconnect the steering v.reversing relaywinding from .ground to cause the relay contacts to fall to their"normal position. kThis causes the steering 1notor93 to be energized forrotation inproper direction to cause clockwise rotation vor4 the .rudder'Itmcause the ship ito'` turn leftback on course and this causes theshaft'13 Yand `the contact disks to be rotated counterclockwise" untilthe grounded contact disk 69 moves vinto Contact with `the finger 63 tocomplete an energizing circuit comprising the current co1lect ing means55 and wires 41, 64 and 85 for the winding of the relay 62. This causesthe movable contacts to be moved upwardly and cause reversal of thesteering motor and the direction of rotah tion of the shaft 13 andcontact disks thereon. The ship is accordingly caused to follow thecourse setting by slight alternate right and left turns of the shipabout the course setting. In other words the ship is caused to huntabout the course setting as determined by the gyroscope; Should the shiptend to roll about its longitudinal 'center line and the pivot axis ofthe inner gimbal the disk contact 19 or the disk contact 8D mounted onthe outer gimbal, depending upon the direction of roll, will 'be movedinto contact with the spring nger 82 on the inner gimbal` Movement ofthe contact disk 19 clockwise into contact with the iinger 82 opens thecircuit connection comprising the wires 85 and 8B to the winding of theerection motor reversing relay 81 to cause the erection motor 23 toapply torque in the proper direction to the outer gimbal about itsvertical axis to cause the inner gimbal to rotate so that the rotor axisis maintained parallel to the transverse center line of the ship. Thiscauses the grounded disk contact 80 on the outer gimbel to contact thespring finger 82 on the inner gimbal to cause re-establishment of thecircuit connection through the winding of the relay 81 comprisingcurrent collecting means 51 and 59 and wires 41, 83, 84, 85 and 85. Thiscauses upward movement of the movable con tacts of the relay 81 andreversa-l cf the erection motor 23 and reverse torque to be applied tothe outer gimbal so that the rotor axis is moved back parallel to thetransverse axis of the ship,4 With this arrangement the axis of therotor is caused to hunt slightly about the transverse center line Aofthe ship at all times.

If it is desired to change the course setting of the ship while in iighta signal of given frequency is transmitted and this signal is picked upby the antenna 31 of the radio receiver to cause energization of thewinding of either of the relays 39 or 4| and closure of the contacts ofeithei relay to cause energization of either the precessing solenoidwinding I5 or I1. Energization of the solenoid winding I5 through theclosed contacts of the relay 39, the current collecting means 49 andwires 41, 50 and 5I applies pull between the winding and its plunger I9and torque is applied between the inner and outergimbals in properdirection to cause precession of the outer gimbal counterclockwise aboutthe vertical axis to cause the spring nger 63 to move into contact withthe contact disk 1I to cause the steering motor to cause the ship toturn left to the new course setting about which it hunts in thepreviously described manner. Conversely energization of the solenoidwinding I1 in response to a received radio signal of a diiferentfrequency through the closed contacts of the relay 4I, currentcollecting means 53 and wires 80 and 6I causes pull to be appliedbetween the winding and its plunger and torque to be applied between theouter and inner gimbals in the reverse direction. This causes clockwiseprecession of the outer gimbal about the vertical axis andthe ringer 53to move into contact with the' grounded contact disk .6 9, to cause theship to turn 4right to the new course setting" about which it hunts aspreviously described.

It will be evident from the above that when either of the precessingwindings i5--I1 is energized, pull is applied to one of the plungers|9-2I and torque in either direction is applied directly between theinner and outer gimbals to cause the outer gimbal to precess about itsvertical axis in either direction. Precession of the outer gimbal ineither direction causes the lug 3| thereon to exert torque on andcompress either of the springs 33 between the lug 3| and one portion ofthe sector gear 21 of the train of gears operable by the erection motor23 secured to the gyro frame I3. Compression of either oi the springs 33causes a slight tilting of the inner gimbal with respect to the outergimbal in either direction and tilting of the rotor axis. This causesthe contact finger 82 on the inner gimbal to move into contact witheither of the contacts 19 or 8G on the outer gimbal to causeenergization and rotation of the erection motor in either directionnecessary 'to relieve the compression of either of the springs 33 due tothe precession of the outer gimbal so that the sector gear 21 ismaintained in the same relative angular position with respect to the lug3| of the outer gimbal and equal compression is maintained on thesprings 33 and the inner gimbal is accordingly rotated in properdirection by this operation of the erectionmotor to cause the rotor axisto be moved back to its original position, parallel to the transversecenter line of the ship, about which it is continuously caused to huntby reason of the contacts 19-8-82 controlling energization and reversalof the erection motor 23 as previously explained. The shaded ends 22 ofthe plungers provide constant torque in either direction between theouter and inner gimbals for the slight movement in either direction ofthe inner gimbal by the erection motor with reference to the outergimbal to maintain the rotor axis parallel to the transverse center lineof the ship.

During precession of the gyroscope in either direction about thevertical axis any banking or rolling of the ship requires theapplication of torque by the erection motor in the proper direction tothe outer gimbal about its vertical axis, depending upon the directionof rotor rotation about its spin axis, to maintain the spin axisparallel to the transverse center line of the ship;

The other modication of directional control system shown in Figure 10and the gyroscopic control means included therein is shown in Figures 5to 7. Y

The gyroscopic control means comprises a rotor 2H which is rotatableabout a horizontal axis in a rotor housing serving as an inner gimbalmember 2I3 by an electric motor 2 I 5. The inner gimbal is pivo'tedabout a horizontal axis, transverse to the rotor axis in an outer gimbalmember 2I1 which is pivoted about a vertical axis in a frame 2I9 of thegyroscope. The frame 2I$i is adapted to be mounted in a ship with thebase parallel to the 'transverse center line or the ship. The frame isenclosed Vin a removable housing cap 22|.

A precession motor 223 is mounted on the outer gimbal and is connectedby reduction gearing also carried on the outer gimbal member as bestshown in Figures 5 and 6. One gear 225 of this gear reduction isrotatable in one arm of a bell crank 221 which is pivoted onf-the outergimbal. -The` alici-,4:76

other arm of lthe bellicrank isi linked to an. armature 229 of an.electromagnet 230 which is also supported on the. outer gimbal so that-upon energization of the electromagnet winding .the gear 225 is movedinto :mesh witha sector ,gear 23| secured to the inner gimbal, asillustrated in Figure 6. When the gear .225 .is engaged with the sectorgear 23| a .contact 233 secured onan insulator on the bellcranlc 22.1 ismoved into contact with another ,contact235 secured onan insulator onYthe outer `gimloal, to control Aenergization of the precession motor223after en gagement ofthe gear y225 with the sector gear 23|.

An erection motor 231 is mounted on theloase of the frame and .isconnected. by reduction gearingY on thebafse of the Yframe. one gear 239of which meshes with a sector gear 24| rotatably mounted on thelowerpivot ofthe outer gimhal, asbest shown in Figures and 8. SpringsV.243 are placed between adjacent spokes of the sector gear 22|, theinner ends of which. bear on a lug 245 on the outer gimbal extendingdownwardly between the spokes of .the sector gear 2M.

Current collecting and controlling means are provided between the frameand the outer and inner` gimbals to control .energization of the rotormotor and to control reversal of precession .and erection motors and tocontrol reversal -of power operated steering mechanism of the ship.These current collecting means. motors and ship steeringrnechanismtogether with the electrical connections therebetween are shown inFigures 5 and 6 and schematically in Figure .10.

.Current collecting means generally indicatedat 241 Vand 249 areprovided between the outer and.

inner gimbals on the axis `of the latter. The collecting means 241includes a Contact 25| secured on an insulator on oneend .of the `outergimbal in coaxial .relation with the .inner gimbal axis and a springng'er 253 securedon a brush holder of the .rotor motor 2|5 and hearingon the contact 25| at a point coaxial with the inner gimbal axis. Thecurrent collecting means 249 is similar to that previously described.and .includes a contact 255 4secured on an .insulator carried on theother end of the-outer girnbal in coaxial relation with the inner gimbalaxis anda spring finger 251secured to the `other brush holder oi therotor motor `2|5 and .bearing on the con-tact 255 at a point coaxialwith the inner gimbal axis.

Another current collecting means indicated generally at 259 is providedadjacent the collecting means 241. This means `serves as a `reversing.switch to control reversalV of' the erection motor and, as best shownin'liguresY 5,v 'I 'and 4l0. .comprises an insulator disk` 26| mountedOn the outer gimbal in coaxial .relation withtl'ie axis of the innergi-mbal and having two contacts ',263 and 255 of semicircu'lar formsecured to the periphery of the disk 26| and a spring .contactY` gixnbaland each of the nngersaresecured to;

an insulator .onthe frame:

The current collecting means A21| serves ,as .a reversing switch tocontrol reversal ofthe ypower steering mechanism of the ship. As best,shown in Figures `6 and 10 this means comprises an insulator disk 215secured on the .lower pivot of the outer gimbal and provided withvsernicircular contact disks 211 and 219 `on the periphery of. theinsulator disk. The adjacent ends of these disk contacts are normallycontacted by a exiblecontact iinger 29| secured on an insulator 283 on`a'gear 295 rotatable .on the base yof the frame about an axis coaxialwith that of the outer .gimbaL The gear 285 .is connected by gears 28.6,281 and 288 on shafts rotatable inthe frame and a follow-up lever 29| issecured to one of the shafts.

Asbest shown in Figure 10 this second modification `of gyroscopiccontrol mechanism .is also controlled by a radio receiver and it also.controls a power operated steering mechanism. Thereceiver and steeringmechanism andthe reversing relays for the steering and erection motorsare identical to those described for controlling the previouslydescribed gyroscopic control mechanisin, but relays of differentconstruction are provided to control precession. o

The rotor motor 2|5 is connected between ground on the frame and thepositive wire 41 by means oi the current collecting means 241 and. 249,two of the slip rings of the'current collecting means 2i! and wires 41,294, 295, 296, 291 and 299. The positive wire l'i is connected to thepositive terminal of the battery 48 having thev negative terminalgrounded.. The field winding of the precession motor 223 is connectedbetween the wires 295 and 298. The winding of the electromagnet 23|) isconnected between the movable contacts of the relays 39' and i throughtwo other vof the slip rings of the current collecting means 269 andwires 399, 30|, 392. and .303. The movable contact of the electromagnet.is connected to the wire 39| and the armature of the precession motor223 is connected between the fixed contact of the electromagnet and thewire 392. rhe spring lngerr251 of the current collecting means 259 isconnected to the wire 295 and the contact disk 265 of this means isconnected by means of another slip ring and ringer of the currentcollecting means 21| and wires 3M and 395 to one winding Vterminal ofthe motor reversing relay 81 of the erection motor 23T. The otherterminal of the winding. of 4the relay Si is grounded. One windingterminal of the steering reversing relay 62 for the steering motor 93 isconnected to the positive wire 'i1 and the other winding terminal of therelay E2 is connected by .a flexible conductor 305 to the spring nger2e! of the. current collecting means 22|. The' disk contact 219 of themeans 2i! Yis connected to the wire 2.98 and is accordingly groundedthrough the lower slip ring and nger. rThe battery connections to the-contacts of the reversing relay 62 and 51 and t0 the erection andsteering motors 231 and vBfiare identical to those previously describedand shown in 'Figure 9.

As previously mentioned, the Contact arrangement of the relays 39 and 4|is different fromv the relays 39 and i, previously described. Each ofthe relays 3 9 and Iii' are providedrwith `two fixed contacts and amovable contact normallyy in engagement with the lower xed contact. .Theupper xed contactsare connected to the positive wire 41,the lower fixedcontacts `are grounded, themovable contacts are separately connected by-separate Wires v30|l1and1303 between'two of" the current collectingmeans indicated generally at 269. Each of the relay windings, however,are connected between ground and a separate output terminal of the radioreceiver ,35 .in identical manner to that previously described withreference to the relays 39 and 4| shown in Figure 9.

The operation of this second modification of gyroscopic control meansand system in which it is included is asfollows: With the rotor rotatingabout the horizontal axis transverse to the course setting andlongitudinal center line of the plane if the ship turns slightly to theleft of the course setting the finger 28| of the current collectingmeans 21| will move out of contact with the contact disk 219 and intocontact `with the contact disk 211 to break `the energizing connectionto the winding of the steering motor reversing relay 62 and cause therelay contacts to fall to the position shown. This causes the motor tobe energized to cause rotation of the rudder counterclockwise in orderto cause the ship to turn right back on the `course setting.Counterclockwise movement of the rudder and turning of the ship to theright causes the disk contacts 211 and 219 to be turned counterclockwiseby the follow-up gear and linkage connection between the rudder 95 andthese contacts until the contact disk 211 moves from under the springnger 28| and the finger is contacted by the contact disk 219. Thiscauses the establishment of a circuit between the positive wire 4'! toground through the winding of relay 92. the wire 30'6, finger 28| anddisk contact 219 which is connected to ground by the wire 299 and thelower collector ringand nger of the current collecting means 21|. Themovable contacts of the relay 62 are moved upwardly upon energization ofthe winding to cause reversal of the steering motor and movement of therudder clockwise to `cause the ship to turn to the left and back oncourse and this causes clockwise rotation of the contact disks 219 and211 to again cause reversal of the steering motor. It will belevidentthat the ship is caused to hunt slightly to the right and left of thecourse in the same manner as with the previously described gyroscopiccontrolling means.

The outer gimbal is likewise rotated by' the l erection motor so thatthe rotor axis is maintained parallel to the transverse center line ofthe ship in a similar manner to that previously described. Any tiltingmovement of the outer gimbal with respect to the vertical axis andtransverse to the rotor axis causes either the disk contact 293 or thedisk contact 295 of the current collecting means 259 to move intocontact wth the contact finger 261 oi this means. When the disks contact263 is in contact with the finger 291 the winding of the reversing relay81 is deenergized to cause the erection motor 231 to apply torque to theouter gimbal with reference to its axis in proper direction to cause theinner gimbal to turn with respect to the outer gimbal to cause the rotoraxis to be maintained parallel to the transverse center line of theship. If the ship rolls in the opposite direction the disk contact 265moves into contact with the iinger 261 to establish a circuit to thewinding of relay 81 through these contacts, and two of the slip ringsand lingers of the current collecting means 269 and wires 41, 294, 295,296, 304 and 305 to ground. rIhis causes the contacts of the relay to bemoved upwardly and cause reversal of the erection motor and applicationoi. torque to the outer gimbal about its axis in the reversedirectiorrto cause the inner gimbal to move in' theop- :posite directionuntil the rotor axis is again parallel to the transverse center line ofthe ship. The rotor axis is accordingly maintained parallel at all timesto the frame of the gyroscope and transverse center line of the ship.

Remote steering of the ship is accomplished in similar' manner aspreviously described by means of radio signals of different frequencypicked up by the receiver to cause energization of the winding of eitherof the relays 39 or 4|. This causes upward movement of the movablecontact by either relay to cause current flow in one direction or theother through the wires 300, 30|, 392 and 393 and the electromagnet 230to cause the armature thereof to cause engagement of the gear traindriven by the precession motor and current iiow through the armaturethereof in one direction ror the other when the contacts operated by theelectromagnet are closed. AThis causes torque to be applied between theinner and outer gimbals in either direction and precession of the rotorand gimbals in opposite directions about the vertical axis. Precessionin one direction causes the disk contact 211 of the current collectingmeans 21| to move into contact with the spring contact 28| of this meansto cause deenergization of the winding of the reversing relay 62 whichcauses rotation of the steering motor 93 and rudder 95 in properdirection to bring the ship back on the new course setting. `By reasonof the follow-up linkage between the rudder and current collectingmeans21| and the turning of the ship the spring contact 28| then contacts thedisk contact 219 to cause energization of the winding of the relay 92through wires 41, 309, 298 and one slip ring and iinger of the currentcollecting means 21| to ground. This causes the direction of rotation ofthe steering motor and rudder to be reversed to cause turning of theship in the opposite direction back on the course setting. The ship willaccordingly be caused to hunt about the course setting as previouslydescribed.

In the two modifications of gyroscopic control devices theelectromagnetic means for controlling precession and erection aredesigned to prevent magnetic leakage therefrom in order to eliminateerrors in the operation of the controlling means, and as the erectionmeans acts at all times to maintain the rotor axis parallel to thetransverse center line of the ship no errors are introduced due to rollor pitch of the ship. Also the arrangement is such that by causingproper rotation of the rotor the banking of the ship when turning causesthe outer gimbal to be turned by the erection motor in the samedirection as the outer gimbal was precessed by either the solenoid ormotor precessing means.

We claim:

1. A directional gyroscope for controlling steering mechanism comprisinga gyroscope rotor supported by gimbals on a frame for normal rotationabout a horizontal axis parallel to the base of the frame, resilientdriving means including a reversible erection motor for applying torqueto the gimbals and rotor in either direction about the vertical axis ofthe frame when the frame is tilted to maintain the rotor axis parallelto the base of the frame, erection motor reversing control contactsbetween the gimbals operable by relative movement between the gimbalsupon tilting of the frame.

2. A directional gyroscope for controlling steering mechanism comprisinga gyroscope rotor supported by gimbals on a frame'for normal rotationabout a horizontal axis parallel to thev base of the frame, resilient.driving means including a reversible erection motor for applying torqueto the gimbalsand rotor in either direction about the vertical axis ofthe frame when the frame is tilted to maintain the rotor axis parallelVto the base of the frame, erection motor reversing control contactsbetween the gimbals operable by relative movement between the gimbalsupon tilting of the frame, ironclad solenoids, and plungers havingshaded poles of stepped form for exerting constant pull and torquebetween the gimbals in either direction to cause precession of the rotorand gimbals in either direction about the vertical axis of the frame,depending upon which solenoid is energized, and control means forselectively controlling energization of the solenoids.

3. A directional gyroscope comprising a gyroscopev rotor supported byinner and outer gimbals for normal rotation about a horizontal axisparallel to the base of a frame, means for applying torque in eitherdirection between the gimbals for causing precession in either directionof the outer gimbal with `respect to the frame about a vertical axis, areversible'erection motor on the frame for applying torque in eitherdirection between the outer gimbal and frame, resilient drive meansconnecting the motor and outer gimbal, and motor reversing control meansoperable upon relative movement between the gimbals for controlling theerection motor tocause the rotor axis to hunt about a preselected'horizontal axis with respect tothe frame.

4. A directional control gyroscope having a rotor supported by inner andouter gimbals on a frame fornormal rotation about an axis parallel tothe base of the frame, precessing means :for applying torque between thegimbals in either directi'on to causeY precession of the outer gimbalabout a; vertical axis with respect to the frame, coaxial connectingmeans on said frame and said outer gimbal to operate said precessingmeans and erection means comprising resilient connecting meansbetweenthe outer gimbal and the frame and additional torque means connectedwith said resilient connecting means for applying torque in eitherdirection between the outer gimbal and frame with respect to thevertical axis and control a l2 Y means operable upon relative movementcfthe inner'and outer gimbals-for controlling said additional'. `torqueapplying means to Amaintain the lro- 'tor aboutv said horizontal axisparallel to th gyroscope frame.

5. A gyroscop'ic directional control system fora steering mechanismcomprising'a frame having a horizontal base, an outer gimbal pivotedabout a vertical axis: in'. the frame, an inner gimbal pivoted about ahorizontal axis in the outer gimbal, a motor driven gyroscope rotormounted for rotation in the inner gimbal transverse to'the inner gimbalpivot axis, a resilient connection be* tween- .the frame and outergimbal, a reversible erection motor to apply torque to the outer gimbalthrough the resilient connection in orderto mainjtain the axis oftherotor parallel to the base or the frame, electrical precessing meansbetween the gimbals for exerting torque directly therebetween to`cause-precession of the rotor and gimbals about the vertical axis oftheouter gimbal, cooperating, electrical energizing and reversing contactslocatedv on the gimbals infcoaxial relation to the axis ofthe innergimbal to reverse the erection motor and cooperating, electricalenergizing con-l tacts located' on the frame and outer gimbal in coaxialrelation t'o the axisof the outer gimbal to energizeY the erection motorand precessing means.

ALBERT W. FISCHER. ARCHIE D. MCDUFFIE.

REFERENCES CITED The 'followingreferences are of record in the le ofthis patent:

UNITED STATES PATENTS-

